xref: /optee_os/core/drivers/pl061_gpio.c (revision 1bb929836182ecb96d2d9d268daa807c67596396)
1 // SPDX-License-Identifier: BSD-2-Clause
2 /*
3  * Copyright (c) 2016, Linaro Limited
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions are met:
8  *
9  * 1. Redistributions of source code must retain the above copyright notice,
10  * this list of conditions and the following disclaimer.
11  *
12  * 2. Redistributions in binary form must reproduce the above copyright notice,
13  * this list of conditions and the following disclaimer in the documentation
14  * and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
20  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26  * POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <assert.h>
30 #include <drivers/pl061_gpio.h>
31 #include <io.h>
32 #include <trace.h>
33 #include <util.h>
34 
35 #ifndef PLAT_PL061_MAX_GPIOS
36 # define PLAT_PL061_MAX_GPIOS	32
37 #endif	/* PLAT_PL061_MAX_GPIOS */
38 
39 #define MAX_GPIO_DEVICES	((PLAT_PL061_MAX_GPIOS + \
40 	(GPIOS_PER_PL061 - 1)) / GPIOS_PER_PL061)
41 
42 #define GPIOS_PER_PL061		8
43 
44 /* gpio register offsets */
45 #define GPIODIR		0x400
46 #define GPIOIS		0x404
47 #define GPIOIBE		0x408
48 #define GPIOIEV		0x40C
49 #define GPIOIE		0x410
50 #define GPIORIS		0x414
51 #define GPIOMIS		0x418
52 #define GPIOIC		0x41C
53 #define GPIOAFSEL	0x420
54 
55 /* gpio register masks */
56 #define GPIOIE_ENABLED		SHIFT_U32(1, 0)
57 #define GPIOIE_MASKED		SHIFT_U32(0, 0)
58 #define GPIOAFSEL_HW		SHIFT_U32(1, 0)
59 #define GPIOAFSEL_SW		SHIFT_U32(0, 0)
60 #define GPIODIR_OUT			SHIFT_U32(1, 0)
61 #define GPIODIR_IN			SHIFT_U32(0, 0)
62 
63 static vaddr_t pl061_reg_base[MAX_GPIO_DEVICES];
64 
65 static enum gpio_dir pl061_get_direction(unsigned int gpio_pin)
66 {
67 	vaddr_t base_addr;
68 	uint8_t data;
69 	unsigned int offset;
70 
71 	assert(gpio_pin < PLAT_PL061_MAX_GPIOS);
72 
73 	base_addr = pl061_reg_base[gpio_pin / GPIOS_PER_PL061];
74 	offset = gpio_pin % GPIOS_PER_PL061;
75 	data = read8(base_addr + GPIODIR);
76 	if (data & BIT(offset))
77 		return GPIO_DIR_OUT;
78 	return GPIO_DIR_IN;
79 }
80 
81 static void pl061_set_direction(unsigned int gpio_pin, enum gpio_dir direction)
82 {
83 	vaddr_t base_addr;
84 	uint8_t data;
85 	unsigned int offset;
86 
87 	assert(gpio_pin < PLAT_PL061_MAX_GPIOS);
88 
89 	base_addr = pl061_reg_base[gpio_pin / GPIOS_PER_PL061];
90 	offset = gpio_pin % GPIOS_PER_PL061;
91 	if (direction == GPIO_DIR_OUT) {
92 		data = read8(base_addr + GPIODIR) | BIT(offset);
93 		write8(data, base_addr + GPIODIR);
94 	} else {
95 		data = read8(base_addr + GPIODIR) & ~BIT(offset);
96 		write8(data, base_addr + GPIODIR);
97 	}
98 }
99 
100 /*
101  * The offset of GPIODATA register is 0.
102  * The values read from GPIODATA are determined for each bit, by the mask bit
103  * derived from the address used to access the data register, PADDR[9:2].
104  * Bits that are 1 in the address mask cause the corresponding bits in GPIODATA
105  * to be read, and bits that are 0 in the address mask cause the corresponding
106  * bits in GPIODATA to be read as 0, regardless of their value.
107  */
108 static enum gpio_level pl061_get_value(unsigned int gpio_pin)
109 {
110 	vaddr_t base_addr;
111 	unsigned int offset;
112 
113 	assert(gpio_pin < PLAT_PL061_MAX_GPIOS);
114 
115 	base_addr = pl061_reg_base[gpio_pin / GPIOS_PER_PL061];
116 	offset = gpio_pin % GPIOS_PER_PL061;
117 	if (read8(base_addr + BIT(offset + 2)))
118 		return GPIO_LEVEL_HIGH;
119 	return GPIO_LEVEL_LOW;
120 }
121 
122 /*
123  * In order to write GPIODATA, the corresponding bits in the mask, resulting
124  * from the address bus, PADDR[9:2], must be HIGH. Otherwise the bit values
125  * remain unchanged by the write.
126  */
127 static void pl061_set_value(unsigned int gpio_pin, enum gpio_level value)
128 {
129 	vaddr_t base_addr;
130 	unsigned int offset;
131 
132 	assert(gpio_pin < PLAT_PL061_MAX_GPIOS);
133 
134 	base_addr = pl061_reg_base[gpio_pin / GPIOS_PER_PL061];
135 	offset = gpio_pin % GPIOS_PER_PL061;
136 	if (value == GPIO_LEVEL_HIGH)
137 		write8(BIT(offset), base_addr + BIT(offset + 2));
138 	else
139 		write8(0, base_addr + BIT(offset + 2));
140 }
141 
142 static enum gpio_interrupt pl061_get_interrupt(unsigned int gpio_pin)
143 {
144 	vaddr_t base_addr;
145 	uint8_t data;
146 	unsigned int offset;
147 
148 	assert(gpio_pin < PLAT_PL061_MAX_GPIOS);
149 
150 	base_addr = pl061_reg_base[gpio_pin / GPIOS_PER_PL061];
151 	offset = gpio_pin % GPIOS_PER_PL061;
152 	data = read8(base_addr + GPIOIE);
153 	if (data & BIT(offset))
154 		return GPIO_INTERRUPT_ENABLE;
155 	return GPIO_INTERRUPT_DISABLE;
156 }
157 
158 static void pl061_set_interrupt(unsigned int gpio_pin,
159 	enum gpio_interrupt ena_dis)
160 {
161 	vaddr_t base_addr;
162 	uint8_t data;
163 	unsigned int offset;
164 
165 	assert(gpio_pin < PLAT_PL061_MAX_GPIOS);
166 
167 	base_addr = pl061_reg_base[gpio_pin / GPIOS_PER_PL061];
168 	offset = gpio_pin % GPIOS_PER_PL061;
169 	if (ena_dis == GPIO_INTERRUPT_ENABLE) {
170 		data = read8(base_addr + GPIOIE) | BIT(offset);
171 		write8(data, base_addr + GPIOIE);
172 	} else {
173 		data = read8(base_addr + GPIOIE) & ~BIT(offset);
174 		write8(data, base_addr + GPIOIE);
175 	}
176 }
177 
178 /*
179  * Register the PL061 GPIO controller with a base address and the offset
180  * of start pin in this GPIO controller.
181  * This function is called after pl061_init().
182  */
183 void pl061_register(vaddr_t base_addr, unsigned int gpio_dev)
184 {
185 	assert(gpio_dev < MAX_GPIO_DEVICES);
186 
187 	pl061_reg_base[gpio_dev] = base_addr;
188 }
189 
190 static const struct gpio_ops pl061_ops = {
191 	.get_direction = pl061_get_direction,
192 	.set_direction = pl061_set_direction,
193 	.get_value = pl061_get_value,
194 	.set_value = pl061_set_value,
195 	.get_interrupt = pl061_get_interrupt,
196 	.set_interrupt = pl061_set_interrupt,
197 };
198 
199 /*
200  * Initialize PL061 GPIO controller
201  */
202 void pl061_init(struct pl061_data *pd)
203 {
204 	COMPILE_TIME_ASSERT(PLAT_PL061_MAX_GPIOS > 0);
205 
206 	assert(pd);
207 	pd->chip.ops = &pl061_ops;
208 }
209 
210 enum pl061_mode_control pl061_get_mode_control(unsigned int gpio_pin)
211 {
212 	vaddr_t base_addr;
213 	uint8_t data;
214 	unsigned int offset;
215 
216 	assert(gpio_pin < PLAT_PL061_MAX_GPIOS);
217 
218 	base_addr = pl061_reg_base[gpio_pin / GPIOS_PER_PL061];
219 	offset = gpio_pin % GPIOS_PER_PL061;
220 	data = read8(base_addr + GPIOAFSEL);
221 	if (data & BIT(offset))
222 		return PL061_MC_HW;
223 	return PL061_MC_SW;
224 }
225 
226 void pl061_set_mode_control(unsigned int gpio_pin,
227 	enum pl061_mode_control hw_sw)
228 {
229 	vaddr_t base_addr;
230 	uint8_t data;
231 	unsigned int offset;
232 
233 	assert(gpio_pin < PLAT_PL061_MAX_GPIOS);
234 
235 	base_addr = pl061_reg_base[gpio_pin / GPIOS_PER_PL061];
236 	offset = gpio_pin % GPIOS_PER_PL061;
237 	if (hw_sw == PL061_MC_HW) {
238 		data = read8(base_addr + GPIOAFSEL) | BIT(offset);
239 		write8(data, base_addr + GPIOAFSEL);
240 	} else {
241 		data = read8(base_addr + GPIOAFSEL) & ~BIT(offset);
242 		write8(data, base_addr + GPIOAFSEL);
243 	}
244 }
245